This is a conscious effort from Nicola Sturgeon to entwine the Brexit process with Scottish independence and seek to turn the 45% into 50%+ by offering an opt out from what she calls "Tory Hard Brexit".

So, the week after next, within days of the Article 50 trigger, Theresa May will also have to decide on blocking a Scottish independence referendum or at the very least finding an elegant method to delay it.

Beware the Ides of March.

But, there are consequences if Article 50 is not triggered until the last week of March.

The European Union is now highly unlikely to be able to hold its EU27 response summit sketching out the negotiating mandate for the European Commission's Michel Barnier until late April or even early May.

Video:MPs reject amendments passed by Lords

This is right in the middle of the French Presidential elections, which could in fact push the summit back to mid May.

Indeed, what is the point of having President Hollande decide the French position among the EU27?